Magnetic sensors, such as Anisotropic Magnetoresistance (AMR) sensors, Giant Magnetoresistance (GMR) sensors, and Hall-Effect sensors play an important role for contactless sensing in various vehicles, such as measurements in subsystems of motor vehicles. For example, AMR sensors may be regularly used for various applications in the vehicle's power-train by, for example, measuring the magnetic fields of various components and making determinations such as the throttle position, based on such measurements. During regular operation, the AMR sensor may compile data based on its measurements of a magnetic field and may send such data to an electrical control unit (ECU) within the vehicle. The ECU may then respond to the received data from the sensor by modifying one or more components within the vehicle, such as when an engine control module (ECM) changes the configuration of a device in the power-train. Such modifications by the ECU may be used by the vehicle to, for example, increase the vehicle's fuel efficiency, acceleration, or power output.
In modern vehicles, however, it is possible for users to tamper with and manipulate vehicle ECUs, such as the ECM. For example, the common practice of “chip tuning” involves the manipulation of the ECM or its related motor management software to increase the power output of the vehicle's engine. However, such unauthorized manipulation of ECUs may, for example, result in higher abrasion of engine components (which are not covered by the warranty) and may also make the vehicle more dangerous, as the vehicle may not have been designed to operated under the manipulated configuration. Manipulation of the ECU may therefore pose problems related to the vehicle's performance and safety, which may therefore decrease the value of the vehicle and cause problems for other drivers.